Improvement of the Quality Assurance Through Automatic Measuring Devices of Dimensions and Camber of the H-shapes

摘要

To improve the quality assurance of the H-shapes after straightening machine, the apparatuses for measuring their dimensions and cambers automatically have been installed in the wide flange mill at Wakayama Work (Sakai Area) of Nippon Steel & Sumitomo Metal Corp. These devices are characterized by the several scanning laser distance meters which provide extremely accurate and quick measurement. Dimension measuring device is composed of seven scanning laser distance meters, each of which measures the distance to the object, and calculates the main dimensions in a cross-sectional of H-shape such as flange width, web height and thicknesses. Camber measuring device is composed of five scanning laser distance meters. Three of them are used for measuring camber in accordance with the length of the H-shapes. The method for calculation is detailed in the full paper. Each measurement-accuracy is 20 = 0.05mm, 0.10mm with sampling frequency of 10 kHz, provided that the object is sufficiently cool and static. The results achieved by installing these devises are as follows: 1) Extreme improvement of quality assurance and production process of H-shapes by accumulating the dimension data every one product. 2) Reduction of the inspection personnel. 3) Shortening of the inspection time.